@mixin scrollbar { // 页面滚动条
    &::-webkit-scrollbar {
        width: 6px;
        height: 6px;
        &-thumb {
            border-radius: 20px;
            background: #a5a5a5;
            box-shadow: inset 0 0 6px hsla(0,0%,80%,.3);
        }
    }
}